Rubik’s Cube Proof Cut to 25 Moves

Last year, a couple of fellas at Northeastern University with a bit of spare time on their hands proved that any configuration of a Rubik’s cube could be solved in a maximum of 26 moves.

Now Tomas Rokicki, a Stanford-trained mathematician, has gone one better. He’s shown that there are no configurations that can be solved in 26 moves, thereby lowering the limit to 25.

Full article here.

Pi Day

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Slabacus (Slide Rule & Abacus Simulator)

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